Chinese factory activity fell for a fourth consecutive month in August to 49.1 points, an official survey showed on Saturday, down from a reading of 49.4 in July. The National Bureau of Statistics purchasing managers’ index (PMI) – a survey of sentiment among factory owners that serves as a leading indicator of the world’s second-largest economy – has also now been below the 50-point threshold for four months. A reading above 50 indicates manufacturing is expanding, while a reading below 50 suggests contraction. In the non-manufacturing sector, which includes the service sector and the constru…